The present invention generally relates to lighters such as pocket lighters used to light cigarettes and cigars or utility lighters used to ignite candles, barbecue grills, fireplaces and campfires, and more particularly to such lighters which resist inadvertent operation or undesirable operation by unintended users.
Lighters used for igniting tobacco products, such as cigars, cigarettes, and pipes, have developed over a number of years. Typically, these lighters use either a rotary friction element or a piezoelectric element to generate a spark near a nozzle which emits fuel from a fuel container. Piezoelectric mechanisms have gained universal acceptance because they are simple to use. U.S. Pat. No. 5,262,697 (xe2x80x9cthe ""697 patentxe2x80x9d) to Meury discloses one such piezoelectric mechanism, the disclosure the ""697 patent is incorporated by reference herein in its entirety.
Lighters have also evolved from small cigarette or pocket lighters to several forms of extended or utility lighters. These utility lighters are more useful for general purposes, such as lighting candles, barbecue grills, fireplaces and campfires. Earlier attempts at such designs relied simply on extended actuating handles to house a typical pocket lighter at the end. U.S. Pat. Nos. 4,259,059 and 4,462,791 contain examples of this concept.
Many pocket and utility lighters have had some mechanism for resisting undesired operation of the lighter by young children. Often, these mechanisms are on/off switches which may shut off the fuel source or may prevent movement of an actuator, such as a push-button, on the lighter. On/off switches which a user positively moves between xe2x80x9conxe2x80x9d and xe2x80x9coffxe2x80x9d positions can be problematic. For example, an adult user may forget to move the switch back to the xe2x80x9coffxe2x80x9d position after use and thereby render the feature ineffective.
Other pocket and utility lighters include a spring-biased blocking latch which arrests or prevents movement of the actuator or push-button. U.S. Pat. Nos. 5,697,775 to Saito and 5,145,358 to Shike et al. disclose examples of such lighters.
There remains a need for lighters which resist inadvertent operation or undesirable operation by unintended users, but which provide each intended user with a consumer-friendly method of operating the lighters so that the lighters appeal to a variety of intended users.
The present invention is directed to a lighter with at least two modes of operation. In either mode of operation, the lighter preferably is operational with no blocking mechanism(s) which arrests or prevents movement of an actuating member.
The present invention in one embodiment relates to a lighter which generally comprises a housing which contains fuel, an actuating member for actuating the lighter, and a movable biasing member. The biasing member preferably moves between a high-actuation-force position and a low-actuation-force position. More specifically, in the high-actuation-force position, the biasing member provides a first opposing force which opposes actuation of the lighter and preferably, when the user moves or repositions the biasing member to the low-actuation-force position, the biasing member provides a second different opposing force which opposes actuation of the lighter.
Preferably the first opposing force provided by the movable biasing member is greater, and optionally significantly greater, than the second opposing force. Optionally, the second opposing force may be substantially zero. The biasing member in the low-actuation-force mode may not oppose movement of the actuating member when the user applies a force thereto to the same extent as in the high-actuation-force mode. In one embodiment, the biasing member in the high-actuation-force position may be operatively associated with, engaged or in contact with, or coupled to the actuating member, and in the low-actuation-force position, the biasing member may be in contact with or disengaged from the actuating member.
In accordance with one embodiment, the actuating member may selectively dispense fuel, activate the ignitor assembly or perform both functions. The lighter optionally may have an ignitor assembly actuated by the actuating member. The ignitor assembly may include a piezoelectric unit. The actuating member may be at least one trigger. In the high-actuation-force position the movable biasing member may resist movement of the trigger to an actuation position by increasing the force necessary to actuate the trigger.
In yet another embodiment, the actuating member may be part of an actuating assembly that includes the trigger, a linking rod, and a pivoting member. The linking rod may be operatively connected to the ignitor assembly, and selectively activates the ignitor assembly. In such an embodiment, the actuating member can be the trigger or the linking rod. The pivoting member may be connected to the housing, disposed between the trigger and the linking rod, and selectively dispense fuel to the nozzle. In the high-actuation-force position the biasing member may contact the linking rod and apply the first opposing force to the linking rod to oppose movement of the linking rod. In the low-actuation-force position, the biasing member may be moved or repositioned and applies a second opposing force which preferably is less than the first opposing force, and optionally may be substantially less than the first opposing force or substantially zero.
In a further aspect, a latch member may be operatively associated with the biasing member. The latch member can be coupled to the housing in a number of ways, such as pivotally, slidably or in a cantilevered fashion. In the cantilevered coupling, one end of the latch member is fixed to the housing while the other end is free to move. Movement of the latch member may move the biasing member between the high-actuation-force position and the low-actuation-force position. The latch member may be separate from or integral with the biasing member, or the biasing member may be moved or repositioned directly by the user.
In an alternate embodiment, the lighter further includes a biasing member with an engaging portion and an actuating assembly with an engaging portion. The biasing member is movable between a first, at rest state and a second state. In the first state, the biasing member engaging portion is associated with the engaging portion of the actuating assembly. In the second state, the engaging portion of the actuating assembly moves the engaging portion of the biasing member. Less than about 10 kg applied to the trigger changes the biasing member from the first state to the second state and activates the ignitor.
This embodiment may further include a valve for dispensing fuel which is biased into a closed position and moveable to an open position. The actuating assembly selectively moves the valve. When in the high-actuation-force position, the biasing member resists or opposes movement of the actuating assembly. If the user applies a force equal to or greater than a first trigger force to the actuating assembly when the biasing member is in the high-actuation-force position, the valve moves from the closed position to the open position. When the biasing member is in the low-actuation-force position, the user may apply a lower second trigger force to the actuating assembly in order to move the valve between such positions.
One preferred aspect of the multi-mode lighter according to at least one embodiment is that after multiple actuations of the lighter, the first and second trigger forces required to operate the lighter in either mode, and more preferably the first trigger force, remains substantially constant. Thus, the first and second opposing forces exerted by the movable biasing member preferably do not substantially decrease with use of the lighter.
According to yet another embodiment of the present invention, the movable biasing member is configured and adapted in the high-actuation-force position to resist movement of the actuating assembly to an operative position and has a predetermined, at rest, length which upon movement of the actuating assembly may change between a first length and a second length. In one embodiment, the biasing member is configured such that its length in a first position is less than its length in a second position such as in, for example, a tension or extendable spring. In another embodiment, the biasing member is configured such that its length in its first position is greater than the length in its second position, as in, for example, a compression spring.
According to yet another embodiment, the lighter comprises a housing having a supply of fuel, an ignitor assembly for igniting the dispensed fuel, an actuating member associated with the housing, and a repositionable biasing member disposed to the housing. A predetermined actuating force is necessary to move the actuating member to an actuation position to actuate the lighter. In a first position, the biasing member is associated with the actuating member such that a first actuating force greater than said predetermined actuating force is required to move the actuating member to the actuation position.
According to a preferred aspect of the multi-mode lighter, the first or high-actuation-force mode preferably relies more on the user""s physical characteristics, and more specifically strength characteristics, while the second or low-actuation-force mode preferably relies more on the user""s cognitive abilities and dexterity. In yet another preferred, but optional, aspect of this lighter, the user may actuate the lighter in the high-actuation-force mode with a single finger. Moreover, according to another preferred, but optional, aspect of this lighter, the user may actuate the lighter in the low-actuation-force mode with two fingers. One further preferred, but optional, feature of the lighter is that actuation of the lighter in the high-actuation-force mode may occur by a different actuation sequence or movement than the actuation sequence or movements which may occur in the low-actuation-force mode.